There are a large number of fluidic oscillators useful for issuing a sweeping fluid stream into ambient. See, for example, Stouffer U.S. Pat. Nos. 4,652,002, 4,508,267, Bray U.S. Pat. Nos. 4,463,904, 4,645,126, Turner U.S. Pat. No. 3,432,102, Walker U.S. Pat. No. 3,507,275, Viets U.S. Pat. No. 3,998,386, Stouffer et al. U.S. Pat. No. RE 33,158, Bauer U.S. Pat. No. 4,157,167, Stouffer U.S. Pat. No. 4,151,155, and Bauer U.S. Pat. No. 4,184,636 are free of feedback channels: Stouffer '155 depends on vortices alternately shed from an island and Bauer '636 uses a reversing chamber feeding a separate output chamber. While Stouffer '155 can be molded in a single molding so that it does not require assembly, its frequency of oscillation is high. In a previous oscillating device called a "Travetron", alternating vortices were formed but these were high pressure devices and the vortices cavitated and the oscillation chamber was wider than it was long. U.S. Pat. No. 4,721,251 discloses a fluidic oscillator having walls defining first and second chambers with the second chamber being stepwise widened from the first chamber and having a "turn" wall for turning the branch flow therein to collide with a deflected main jet to push the main jet in an opposite direction. The laterally spaced sidewalls of the first chamber serve as sucking and deflecting walls. The second chamber and its laterally displaced sidewalls make the unit wider than its length.
The object of the present invention is to provide an improved fluidic oscillating nozzle for dispersal or distribution of fluid, and more particularly, to a single feedback-free oscillator which operates a low pressure and which can be made at lower cost, preferably in a single molding and does not require expensive assembly equipment and which eliminates problems from sealing. The unit is simpler than prior art designs and has a good fan angle.